Algorithm to Calculate Pipe Ovality

Difference in thickness can be attributed to eccentricity error too. to get the ovality values you need to specify difference in diameter,(inner or outer). also you need to be sure that there is no lobbing in your pipe as you cant measure lobbing with an ordinary micrometer.

Thanks for the info, but, if I just want to use thickness measurements to check for ovality is it possible? Forgot to add I also have the nominal wall thickness.

Wall thickness is the function of two diameters OD and ID,where as ovality is just related to any one diameter that may be ID or OD or both,

If you want to calculate ovality from thickness values you are having then you must be sure that.

Pipe is absolutely concentric.

Diameter other then you are concerned about is exactly round.

If you are not sure about these conditions I advice you not to try to calculate ovality from thickness values,

Brilliant advice, many thanks Rakesh. I now realise I need to use OD measurements as you stated. Thanks again, this resolves my query.

Lianne

Rakesh,

Will you please tell me what the result should be for the following, so I can verify my results. Many thanks. All measurements in mm.

Min OD: 32.4

Max OD: 33.7

Nom (on straight): 34

Brilliant, I got the 3.82 result. Thank-you so much for your help.

Kind regards, Lianne

may i know the torelance limit for ovality

Roger, very useful info - stored that to my hdd.

Hello Roger Pink:

That info and diagrams are really interesting. I too have saved it, thank you.

Take care.........

Hi,

Optimess engineering germany www.optimess.com are develloped DKM device: Deformation and calibre measurement device.

This allow you to determinate de ovality along the pipe.

My interest lies in calculating the force required to prevent that the OD is increased when cold bending pipelines and would appreciate some guidance. This is the force that pipeline bending machines are designed for and would the case for our product described at www.oceanfloat.com

Thanks